US4406141A - Straightening apparatus for steel pipes and the like - Google Patents

Straightening apparatus for steel pipes and the like Download PDF

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Publication number
US4406141A
US4406141A US06/291,954 US29195481A US4406141A US 4406141 A US4406141 A US 4406141A US 29195481 A US29195481 A US 29195481A US 4406141 A US4406141 A US 4406141A
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United States
Prior art keywords
straightener
roll
rolls
straighteners
steel pipe
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
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US06/291,954
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English (en)
Inventor
Masachika Numano
Shinji Akita
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JFE Engineering Corp
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Nippon Kokan Ltd
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Assigned to NIPPON KOKAN KABUSHIKI KAISHA, 1-2, MARUNOUCHI-1-CHOME, CHIYODA-KU, TOKYO, JAPAN A CORP. OF JAPAN reassignment NIPPON KOKAN KABUSHIKI KAISHA, 1-2, MARUNOUCHI-1-CHOME, CHIYODA-KU, TOKYO, JAPAN A CORP. OF JAPAN ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: AKITA, SHINJI, NUMANO, MASACHIKA
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Publication of US4406141A publication Critical patent/US4406141A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D3/00—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts
    • B21D3/02—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts by rollers
    • B21D3/04—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts by rollers arranged on axes skew to the path of the work

Definitions

  • the present invention relates to a roll-type straightening apparatus for straightening the bend produced in steel pipes, round bars and the like (hereinafter simply referred to as steel pipes) during their manufacture.
  • a straightening machine is arranged at the rear of a rolling mill so as to straighten the bend produced in steel pipes during the rolling operation.
  • a plurality of straighteners are arranged in tandem and each of the straighteners includes a set of relatively small concave rolls arranged one upon another with a predetermined spacing therebetween and mounted to make a predetermined angle with the axis. All the rolls or some of the rolls are driven by motors to rotate in a predetermined direction.
  • a straightening machine of the type comprising a combination of concave and convex rolls has been used in some applications.
  • this type of machine is undoubtedly much effective in straightening the ends of steel pipes, it has a fatal disadvantage that the speed of straightening is low.
  • this straightening machine can increase its straightening speed by increasing the angle made by the top and bottom rolls with the axis, the contact area with a steel pipe will be reduced and the number of times the steel pipe is bent will be decreased thus making it difficult to straighten the bend in the pipe ends.
  • this type of machine is disadvantageous in that while the pair of rolls comprising a combination of concave and convex rolls is arranged centrally so as to straighten a steel pipe over its entire length (several tens meters) and this has a greater effect in straightening the pipe ends, the straightening operation is slow and inefficient and the machine cannot be incorporated in a high-speed steel pipe production line.
  • an improved straightening apparatus for steel pipes and the like which comprises a straightener including a combination of concave rolls and another straightener including a combination of concave roll and a convex roll and arranged at least at one or the other of the entry and exit ends of the first straightener whereby when one or the other of the two straighteners presses a steel pipe, the pressure application of the other straightener is released.
  • FIG. 1 is a schematic diagram for explaining the principle of a straightening apparatus according to the present invention
  • FIG. 2 shows a plurality of diagrams useful for explaining the operation of the apparatus shown in FIG. 1;
  • FIG. 3 is a front view of an embodiment of the straightening apparatus according to the invention.
  • FIG. 4 is a side view of FIG. 3;
  • FIG. 5 is a sectional view showing by way of example a roll lifting mechanism
  • FIG. 6 is a diagram showing the condition of a steel pipe prior to its straightening.
  • numeral 1 designates a first straightener of the previously mentioned known type comprising a combination of concave rolls 1 to 6, II a second straightener comprising a combination of a concave roll 7 and a convex roll 8, and III a third straightener of the same construction as the second straighter II.
  • first straightener I may be comprised of the top and bottom rolls of different sizes and also the number of rolls is not limited to 6.
  • the present invention features that in the straightening apparatus constructed as described above, the top rolls 1, 3, 5, 7 and 9 of the straighteners I, II and III are separately movable vertically in the respective straighteners independently of one another by means of hydraulic mechanisms, electro-mechanical mechanisms or the like.
  • the bottom rolls 2, 4, 6, 8 and 10 may be moved vertically or alternatively all of the top and bottom rolls 1 to 6, 7, 8, 9 and 10 may be made vertically movable.
  • the straighteners II and III are provided with guide shoes.
  • the top roll 9 of the straightener I is lowered and thus the straightening action is applied to the rear end portion of the steel pipe P while moving it forward at a relatively low speed. In this way, the steel pipe P is straightened over its entire length with a high degree of accuracy.
  • the present invention is not intended to be limited to this order.
  • FIG. 3 is a front view of an embodiment of the invention and FIG. 4 is its side view.
  • numeral 11 designates a base plate on which an inverted L-shaped frame 12 is vertically mounted, and supports 13 and 14 are arranged between the front part of the frame 12 and the base plate 11.
  • Numerals I, II and III designate first, second and third straighteners.
  • small concave rolls 1 and 2 are arranged to oppose each other at a predetermined angle (the rolls are shown planarily in the Figure).
  • the roll 1 is attached to the frame 12 by means of a supporting arm 15 and a lifting mechanism 16 and the roll 2 is fixed to the base plate 11 by means of a supporting arm 17 and a supporting block 18.
  • a large concave roll 7 is attached to the frame 12 by means of a supporting arm 27 and a lifting mechanism 28 and a large convex roll 8 is fixed to the base plate 11 by means of a supporting arm 29.
  • a concave roll 9 and a convex roll 10 of the third straightener III are respectively attached to the frame 12 and the base plate 11.
  • the large diameter portion and the length of the rolls 1 to 6 of the first straightener I are respectively 380 mm ⁇ and 480 mm
  • the large diameter portion and the length of the rolls 7 to 10 of the second and third straight II and III are respectively 800 mm ⁇ and 1,000 mm.
  • FIG. 5 shows an exemplary construction of the lifting mechanism 16 of the roll 1 in the first straightener I.
  • the roll 1 is supported on the supporting arm 15 by means of bearings 33 and 34, and the supporting arm 15 is fixedly mounted on a supporting cylinder 35 which is vertically slidably fitted in an outer cylinder 36 fixed to the frame 12.
  • Numeral 37 designates a stationary block which is hermetically fixedly mounted in the supporting cylinder 35, and 38 an oil hydraulic pipe having its one end fixed to the stationary block 37 and its other end connected to a hydraulic unit (not shown).
  • Numeral 39 designates a screwdown shaft including an external thread 40 formed on substantially the central portion and splines 41 formed on the upper part, and a piston 42 disposed within the supporting cylinder 35 is attached to the lower end of the shaft 39 through a bearing 43.
  • Numeral 45 designates an oil hydraulic chamber which is formed between the stationary block 37 and the piston 42 and communicated with the oil hydraulic pipe 38.
  • Numeral 46 designates a worm gear attached to the screwdown shaft 39 by means of the splines 41 and engaged with a worm 47 which is operated by a motor (not shown).
  • the operation of the lifting mechanism is as follows.
  • the hydraulic pressure supplied into the oil hydraulic chamber 45 from the oil hydraulic pipe 38 is increased so that the roll 1 is lowered by means of the stationary block 37, the supporting cylinder 35 and the supporting arm 15.
  • the worm 47 and the worm gear 46 are rotated so that the screwdown shaft 39 and the piston 42 attached to the former are lowered.
  • the stationary block 37, the supporting cylinder 35, the supporting arm 15 and the roll 1 are lowered by means of the hydraulic pressure in the oil hydraulic chamber 45 so that the clearance between the top and bottom rolls 1 and 2 is adjusted to suit the outer diameter of the steel pipe P and the roll 1 is caused to apply a proper pressure.
  • the hydraulic pressure supplied into the oil hydraulic chamber 45 is decreased so that the roll 1 is raised slightly into a free condition and the pressure application is released. If it is desired to again allow the roll 1 to apply a proper pressure, the hydraulic pressure in the oil hydraulic chamber 45 is increased so that the roll 1 is slightly lowered and it is held in position which applies a proper pressure.
  • such ordinary means as rotating the supporting cylinder 35 is used to vary the angle of the roll 1.
  • numerals 51 and 52 designate driving mechanisms for rotating the respective rolls, and shafts 53 and 54 which are driven by motors (not shown) through universal joints are each connected to one of the rolls of the straighteners I, II and III.
  • lifting mechanisms 20 and 24 of the other rolls 3 and 5 of the first straightener I are identical with the lifting mechanism 16, and also the lifting mechanisms 28 and 31 of the rolls 7 and 9 of the second and third straighteners II and III are similar in construction to the lifting mechanism 16 of the roll 1.
  • the worm 47 and the worm gear 46 are rotated through the operation of the motor so that the screwdown shaft 39 and the supporting cylinder 35 are lowered and each of the rolls 1,3, 5 and 7 is allowed to provide a suitable amount of pressure, and the motor of the lifting mechanism 31 is rotated in the reverse direction so that the roll 9 of the third straightener III is raised.
  • a sensor Disposed at the entry side of the second straightener II is a sensor (not shown) for sensing the passage of the forward end of the steel pipe P by means of light, for example, so that when the forward end of the steel pipe P passes the sensor, this is sensed and a timer is operated.
  • the forward end of the steel pipe 1 is introduced into the second straightener II so that the bend in the pipe end portion is straightened and then fed into the first straightener I, in accordance with the predetermined conditions the hydraulic pressure in the oil hydraulic chamber of the lifting mechanism 28 in the second straightener II is instantly decreased and the roll 7 is raised.
  • the steel pipe P is straightened by the first straightener I practically over its entire length at a high speed (see (B) of FIG. 2).
  • the feeding speed of the steel pipe P is set to a predetermined speed for each of the straighteners I, II and III so that if the necessary conditions are predetermined in accordance with the time of operation of the timer as a reference point, the steel pipe P can be straightened automatically in such a manner that the foward and rear end portions or the limited areas are straightened at a relatively low speed and the straightening of practically the entire length (several tens meters) are straightened at a high speed, thus accomplishing the straightening of the steel pipe as a whole accurately at a high speed which is matched to the speed of the modern steel pipe production lines.
  • various means may be used for vertically moving the rolls in the straighteners I, II and III.
  • the timer is operated as soon as the steel pipe P is introduced into the second straightener II, whereby in response to an electronic computer having the various conditions such as the feeding speeds of the straighteners I, II and III preset thereinto, the roll 7 of the second straightener II is raised at the expiration of a predetermined time after the beginning of the introduction and then the roll 9 of the third straightener III is lowered at the expiration of another predetermined time.
  • the rolls are moved vertically, in the case of a straightening apparatus in which the rolls are arranged on both sides the rolls must of course be moved laterally.
  • the concave roll is arranged at the top and the convex roll is arranged at the bottom, the positions of the rolls may be reversed.
  • the guide shoes included in the straighteners II and III the guide shoes may be advantageously moved laterally along with the vertical movement of the top rolls.
  • the straighteners II and III each comprising a set of concave and convex rolls are respectively arranged in the entry and exit sides of the straightener I, one of the straighteners II and III may be eliminated. Still further, while one form of the drive mechanisms for vertically moving the rolls is shown in FIG. 5, the present invention is not intended to be limited to it and any other mechanism may of course be used provided that the similar function is served.
  • the straightening of a steel pipe is accomplished for the most part by the straightener of the ordinary type comprising the concave rolls at a high speed and the pipe end portions are straightened by the straighteners arranged at the front and back of the ordinary straightener and each comprising the concave and convex rolls, thus straightening the steel pipe in a short period of time with a high degree of accuracy.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Wire Processing (AREA)
  • Straightening Metal Sheet-Like Bodies (AREA)
US06/291,954 1980-08-21 1981-08-11 Straightening apparatus for steel pipes and the like Expired - Fee Related US4406141A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP1980117442U JPS5744624U (nl) 1980-08-21 1980-08-21
JP55-117442[U] 1980-08-21

Publications (1)

Publication Number Publication Date
US4406141A true US4406141A (en) 1983-09-27

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Family Applications (1)

Application Number Title Priority Date Filing Date
US06/291,954 Expired - Fee Related US4406141A (en) 1980-08-21 1981-08-11 Straightening apparatus for steel pipes and the like

Country Status (7)

Country Link
US (1) US4406141A (nl)
JP (1) JPS5744624U (nl)
CA (1) CA1160550A (nl)
DE (1) DE3132815C2 (nl)
FR (1) FR2488819B1 (nl)
GB (1) GB2085781B (nl)
IT (1) IT1139407B (nl)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0182003A2 (de) * 1984-11-14 1986-05-28 Th. Kieserling & Albrecht GmbH & Co. Schrägrollenrichtmaschine mit mehr als 2 Richtrollen
EP0431775A2 (en) * 1989-11-22 1991-06-12 Nkk Corporation Method of continuous finishing of pipe
US6412323B2 (en) * 2000-01-07 2002-07-02 Sms Eumuco Gmbh Cross-roll straightener
KR100456073B1 (ko) * 2001-10-09 2004-11-12 심학보 고무판의 연속 제조장치
US20120304724A1 (en) * 2010-03-29 2012-12-06 Sumitomo Metal Industries, Ltd. Method for straightening tube and straightening roll
CN104971966A (zh) * 2014-04-05 2015-10-14 薄占川 组合曲线多斜辊钢管矫直机
CN105980073A (zh) * 2014-01-29 2016-09-28 山特维克原料技术德国公开股份有限公司 辊式矫直机和生产伸长的线形构件的方法
CN106623503A (zh) * 2015-07-30 2017-05-10 惠山区前洲双谐机械配件厂 圆棒矫直机
CN109128687A (zh) * 2018-11-15 2019-01-04 中国建筑第四工程局有限公司 一种钢管修复装置
CN111347251A (zh) * 2020-03-19 2020-06-30 张家港市振原制管有限公司 一种钢管矫正加工装置及使用方法
CN112275841A (zh) * 2020-11-19 2021-01-29 浙江义腾特种钢管有限公司 一种全自动钢管矫直装置
CN113714335A (zh) * 2021-08-31 2021-11-30 江苏江海机床集团有限公司 一种带有实时检测矫直效果的钢管矫直机
CN116351911A (zh) * 2023-06-02 2023-06-30 广东思豪流体技术有限公司 一种铝合金管道的矫直工装及其操作方法
CN116408368A (zh) * 2023-03-31 2023-07-11 广东金铝轻合金股份有限公司 一种基于反向挤压成型的铝制管矫直器

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112718928A (zh) * 2020-12-10 2021-04-30 中国重型机械研究院股份公司 一种圆材矫直装置及其矫直方法

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2357570A1 (de) * 1973-07-19 1975-01-30 Schwermasch Rau Wildau Walzenanstellung fuer zweiwalzenrichtmaschinen
US4057988A (en) * 1976-08-16 1977-11-15 Kotaro Tsukamoto Rectifying equipment of bar material

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE605439C (de) * 1930-11-15 1934-11-10 Sutton Eng Co Verfahren zum Kaltbearbeiten von Werkstuecken kreisrunden Querschnittes durch Richten, Runden, Glaetten und Polieren im Schraegwalzwerk
US2147589A (en) * 1936-06-30 1939-02-14 Frederic Schaefer Apparatus for straightening bars, rounds, or the like
FR981362A (fr) * 1948-12-30 1951-05-25 Procédé pour la déformation de matières thermoplastiques
GB1231383A (nl) * 1967-06-09 1971-05-12
DE1910879C3 (de) * 1969-03-04 1978-12-07 Th. Kieserling & Albrecht, 5650 Solingen Richtmaschine für langgestreckte Werkstücke runden Querschnitts
FR2258912B1 (nl) * 1974-01-25 1979-01-05 Vallourec
DE2902827C2 (de) * 1979-01-23 1984-05-10 Mannesmann AG, 4000 Düsseldorf Schrägwalzenrichtmaschine für Rohre

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2357570A1 (de) * 1973-07-19 1975-01-30 Schwermasch Rau Wildau Walzenanstellung fuer zweiwalzenrichtmaschinen
US4057988A (en) * 1976-08-16 1977-11-15 Kotaro Tsukamoto Rectifying equipment of bar material

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0182003A2 (de) * 1984-11-14 1986-05-28 Th. Kieserling & Albrecht GmbH & Co. Schrägrollenrichtmaschine mit mehr als 2 Richtrollen
EP0182003A3 (de) * 1984-11-14 1987-03-25 Th. Kieserling & Albrecht GmbH & Co. Schrägrollenrichtmaschine mit mehr als 2 Richtrollen
EP0431775A2 (en) * 1989-11-22 1991-06-12 Nkk Corporation Method of continuous finishing of pipe
EP0431775A3 (en) * 1989-11-22 1991-07-10 Nkk Corporation Method of continuous finishing of pipe
US6412323B2 (en) * 2000-01-07 2002-07-02 Sms Eumuco Gmbh Cross-roll straightener
KR100456073B1 (ko) * 2001-10-09 2004-11-12 심학보 고무판의 연속 제조장치
US20120304724A1 (en) * 2010-03-29 2012-12-06 Sumitomo Metal Industries, Ltd. Method for straightening tube and straightening roll
US8783085B2 (en) * 2010-03-29 2014-07-22 Nippon Steel & Sumitomo Metal Corporation Method for straightening tube and straightening roll
CN105980073A (zh) * 2014-01-29 2016-09-28 山特维克原料技术德国公开股份有限公司 辊式矫直机和生产伸长的线形构件的方法
CN104971966A (zh) * 2014-04-05 2015-10-14 薄占川 组合曲线多斜辊钢管矫直机
CN106623503A (zh) * 2015-07-30 2017-05-10 惠山区前洲双谐机械配件厂 圆棒矫直机
CN109128687A (zh) * 2018-11-15 2019-01-04 中国建筑第四工程局有限公司 一种钢管修复装置
CN111347251A (zh) * 2020-03-19 2020-06-30 张家港市振原制管有限公司 一种钢管矫正加工装置及使用方法
CN112275841A (zh) * 2020-11-19 2021-01-29 浙江义腾特种钢管有限公司 一种全自动钢管矫直装置
CN113714335A (zh) * 2021-08-31 2021-11-30 江苏江海机床集团有限公司 一种带有实时检测矫直效果的钢管矫直机
CN113714335B (zh) * 2021-08-31 2023-03-21 江苏江海机床集团有限公司 一种带有实时检测矫直效果的钢管矫直机
CN116408368A (zh) * 2023-03-31 2023-07-11 广东金铝轻合金股份有限公司 一种基于反向挤压成型的铝制管矫直器
CN116408368B (zh) * 2023-03-31 2023-11-14 广东金铝轻合金股份有限公司 一种基于反向挤压成型的铝制管矫直器
CN116351911A (zh) * 2023-06-02 2023-06-30 广东思豪流体技术有限公司 一种铝合金管道的矫直工装及其操作方法
CN116351911B (zh) * 2023-06-02 2023-08-08 广东思豪流体技术有限公司 一种铝合金管道的矫直工装及其操作方法

Also Published As

Publication number Publication date
FR2488819A1 (fr) 1982-02-26
GB2085781B (en) 1984-06-20
IT1139407B (it) 1986-09-24
JPS5744624U (nl) 1982-03-11
GB2085781A (en) 1982-05-06
CA1160550A (en) 1984-01-17
DE3132815A1 (de) 1982-04-08
IT8123586A0 (it) 1981-08-20
FR2488819B1 (fr) 1985-11-15
DE3132815C2 (de) 1986-03-13

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